138 D. J. SCOURFIELD ON THE ENTOMOSTRACA OF NORTH WALES. 



hand we have many forms living here which do not figure in the 

 Welsh list, but of course it would be very unwise, looking to the 

 large amount of collecting that has been done here compared with 

 North Wales, to put these forward as evidence of the difference 

 between the two faunas. Nevertheless one cannot help being 

 struck by the fact that such familiar species to us as Daphnia 

 pulex, Bosmina longirostris, etc., should be conspicuous only by their 

 absence from the records from North Wales. It is also very 

 strange, by the way, that the list of Cladocera should contain no 

 representative of the so-called Hyalodaphnias, e.g., Daphnia 

 Jcahlbei'gensis, etc. Of all places in the United Kingdom where I 

 should have thought it perfectly safe to predict the occurrence of 

 these typically "pelagic " creatures, it would have been the lakes 

 of North Wales. The list of Ostracoda shows no peculiar forms, 

 as every one of the species given has also been found in this part 

 of the country. Of Copepoda, however, the present record contains 

 three species that are characteristic so far as the present comparison 

 is concerned, viz. : Diaptomus hii-cus, Canthocamptus MacAndrewce, 

 and Car,thocamptns hirticornis. The essentially brackish water 

 species have been left out of account, as I do not think they have 

 been properly worked on our coasts. It may further be interesting 

 to note that not a single characteristic species of Cyclops has been 

 recorded. 



I should have liked to have given some details as to the charac- 

 teristic Entomostracan faunas of the larger lakes, of the high 

 mountain tarns, of bog-pools, of mosses and algse, etc., but my 

 records from individual localities are necessarily for the most part 

 so meagre that it is useless to attempt anything of the kind at 

 present. The most that can be done will be to give an account of 

 the fauna of the Llanberis Lakes, Llyn Padarn and Llyn Peris, 

 which have been more worked than any of the others. They may 

 probably be taken as typical examples of the larger Welsh Lakes, 

 and, as they are so intimately connected, it will be quite good 

 enough for present purposes to consider them together. I will 

 attempt to classify the species according to whether they were 

 found to belong to the " pelagic," " littoral," or '• bottom" fauna. 

 The phrase " bottom " fauna, it should be explained, includes those 

 species collected from the bottom of the lakes at some distance 

 irom the shore, in depths var)ii.y from ^5 to 100 feet, or there- 

 abouts. 



